小牛胸腺DNA聚合酶α引发和未引发的聚（dA-dT）合成

Primed and unprimed synthesis of poly (dA-dT) by calf thymus DNA polymerase alpha.

作者信息

Henner D, Further J J

出版信息

J Biol Chem. 1977 Mar 25;252(6):1932-7.

Abstract

The primed and unprimed synthesis of poly(dA-dA-dT) by calf thymus DNA polymerase alpha (DNA nucleotidyltransferase; deoxynucleoside triphosphate: DNA deoxynucleotidyltransferase EC 2.7.7.7) has been compared to replication of activated DNA. Synthesis of poly(dA-dT) by alpha-polymerase is both autocatalytic and exponential. The rate of synthesis of poly(dA-dT) is markedly affected by the Mg2+ concentration and has a higher temperature optimum than replication of activated DNA, implicating "slippage" as a necessary part of poly(dA-dT) replication. Calf thymus 24,000-dalton unwinding protein influences poly(dA-dT) synthesis by increasing both the exponential rate constant and the rate of linear synthesis. Single-stranded template poly(dA-dT) is provided alpha-polymerase by both "strand slippage" and melting by unwinding protein.

摘要

已将小牛胸腺DNA聚合酶α（DNA核苷酸转移酶；脱氧核苷三磷酸：DNA脱氧核苷酸转移酶EC 2.7.7.7）对聚（dA-dA-dT）的引发合成和未引发合成与活化DNA的复制进行了比较。α-聚合酶合成聚（dA-dT）既是自动催化的又是指数性的。聚（dA-dT）的合成速率受到Mg2+浓度的显著影响，并且具有比活化DNA复制更高的最适温度，这意味着“滑动”是聚（dA-dT）复制的必要部分。小牛胸腺24,000道尔顿解旋蛋白通过增加指数速率常数和线性合成速率来影响聚（dA-dT）的合成。单链模板聚（dA-dT）通过“链滑动”和解旋蛋白的解链作用为α-聚合酶提供。